Pull "Third Round of Renesas ARM Based SoC Fixes for v4.13" from Simon Horman:
Fix deadlock in regulator quirk for R-Car Gen 2 SoCs
The da9063/da9210 regulator quirk for R-Car Gen2 boards uses a bus
notifier, and unregisters the notifier when it is no longer needed.
However, a notifier must not be unregistered from within the call chain.
This bug went unnoticed, as blocking_notifier_chain_unregister() didn't
take the semaphore during early boot. This is no longer the case as of
upstream commit
1c3c5eab171590f8 ("sched/core: Enable might_sleep() and
smp_processor_id() checks early") and a deadlock occurs.
* tag 'renesas-fixes3-for-v4.13' of https://git.kernel.org/pub/scm/linux/kernel/git/horms/renesas:
ARM: shmobile: rcar-gen2: Fix deadlock in regulator quirk
{
struct device *dev = data;
struct i2c_client *client;
+ static bool done;
u32 mon;
+ if (done)
+ return 0;
+
mon = ioread32(irqc + IRQC_MONITOR);
dev_dbg(dev, "%s: %ld, IRQC_MONITOR = 0x%x\n", __func__, action, mon);
if (mon & REGULATOR_IRQ_MASK)
remove:
dev_info(dev, "IRQ2 is not asserted, removing quirk\n");
- bus_unregister_notifier(&i2c_bus_type, nb);
+ done = true;
iounmap(irqc);
return 0;
}